Datasheet

Operating Modes and Resource Mapping
Background Debug Mode
MC68HC912D60A — Rev. 3.1 Technical Data
Freescale Semiconductor Operating Modes and Resource Mapping 75
the regular system vectors while BDM is active. While BDM is active, the
user memory from $FF00 to $FFFF is not in the map except through
serial BDM commands.
MODE controls the MCU operating mode and various configuration
options. This register is not in the map in peripheral mode
SMODN, MODB, MODA — Mode Select Special, B and A
These bits show the current operating mode and reflect the status of
the BKGD, MODB and MODA input pins at the rising edge of reset.
SMODN is Read anytime. May only be written in special modes
(SMODN = 0). The first write is ignored;
MODB, MODA may be written once in Normal modes (SMODN = 1).
Write anytime in special modes (first write is ignored) – special
peripheral and reserved modes cannot be selected.
Bit 7654321Bit 0
SMODN MODB MODA ESTR IVIS EBSWAI 0 EME
RESET:00011001Special Single Chip
RESET:00111001Special Exp Nar
RESET:01011001 Peripheral
RESET:01111001Special Exp Wide
RESET:10010000Normal Single Chip
RESET:10110000Normal Exp Nar
RESET:11110000Normal Exp Wide
MODE — Mode Register $000B